Parallax opens Propeller design as Verilog source code. The Propeller 1 (P8X32A) is now a 100% open multicore microcontroller, including all of the hardware and tools: Verilog code, Spin interpreter, PropellerIDE and SimpleIDE programming tools, and compilers. The Propeller 1 may be the most open chip in its class. Here is a live demo.